<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      var a = '全局变量';
      function father() {
        var b = '局部变量';
        // console.log(c);
        function son() {
          var c = '1111';
          // console.log(a);
          console.log(b);
        }
        son();
      }
      father();
    </script>
  </body>
</html>
